At present, a solid-state imaging device as is represented by a CMOS image sensor is used for various applications such as a digital still camera, video movie camera or monitoring camera. It is required for a device using the above image sensor to be able to photograph a dark subject with a high S/N ratio when the subject is photographed and stably attain a high output resolution of an image when a sufficiently bright subject is photographed. Further, in recent years, since a reduction in the size of the camera and high resolution thereof are required, the pixel size of the image sensor tends to be reduced.